Search Results (32)

Background/Objectives: Parabens are widely used preservatives detected at trace levels in drinking water. Although their endocrine-disrupting effects are well established, their long-term impact on environmental bacteria remains poorly understood. This study investigated the effects of parabens on changes in bacterial phenotypic virulence traits and antimicrobial tolerance of bacteria within drinking water biofilms. Methods: Acinetobacter calcoaceticus and Stenotrophomonas maltophilia biofilms were grown on polyvinyl chloride coupons for 26 days under exposure to methyl- (MP), propyl- (PP), butyl-paraben (BP), or a paraben mixture (MIX) at 0.15 µg/L. Biofilm regrowth and virulence-associated traits, including motility (swimming, swarming, and twitching), extracellular enzymes (gelatinase, protease, and lipase), and siderophore production, were evaluated. The effect of prolonged MP exposure (10 weeks) on antimicrobial tolerance was assessed. Results: In A. calcoaceticus, MP reduced biofilm biomass by 32%, whereas MIX increased biomass by 25% and culturability (1.1-fold). S. maltophilia showed increased biofilm culturability with PP (50%), and increased biomass of 2.6-, 2.4-, and 1.8-fold for PP, BP, and MIX, respectively. Biofilm cells exhibited higher virulence factor production than planktonic counterparts. S. maltophilia biofilm cells exposed to BP and MIX showed enhanced swimming and swarming motility, with halo diameters up to fivefold larger than controls. Lipase production increased under BP and MIX exposure, whereas MP exposure reduced it. A MP-induced reduction in motility was observed for A. calcoaceticus and S. maltophilia. Long-term MP exposure results in reduced susceptibility to ceftazidime and minocycline in A. calcoaceticus. Conclusions: Environmentally relevant concentrations of parabens can modulate bacterial virulence traits, increasing biofilm formation, motility and lipase production, and antimicrobial tolerance. Full article

Background: Exposure of pregnant women to stress and endocrine-disrupting chemicals (EDCs) during pregnancy can have a substantial impact on mother and infant health. We investigated the concentrations of EDCs, such as parabens (PBs) and triclosan (TCS), as well as stress hormones (cortisone and cortisol), across pregnancy trimesters and examined their associations with maternal average telomere length (TL). Methods: Hair samples from 49 postpartum women were analyzed using liquid chromatography–mass spectrometry (LC-MS) to quantify EDCs and stress hormone concentrations. Results: The mean methyl paraben concentrations in the hair of postpartum women were prevalent across all pregnancy trimesters, while butyl paraben was detected at the lowest levels. The mean concentration of PBs followed the order methyl > propyl > ethyl > benzyl > butyl paraben across pregnancy trimesters. We found that ethyl paraben and triclosan were each positively and significantly associated with cortisol levels in postpartum women’s hair. Consistent with this, the mean cortisone concentration gradually increased from the first to the third pregnancy trimester, whereas cortisol reached the highest mean concentration at the second trimester. A significant positive association between cortisol and cortisone levels was observed. Further analyses revealed that mothers’ average TL was positively associated with ethylparaben and triclosan levels and inversely associated with benzylparaben levels. Last but not least, we found that cortisol/cortisone levels were positively associated with postpartum women’s TL in a statistically significant manner. Conclusions: In the present study, prenatal exposure to stress hormones and EDCs appears to exert a statistically significant impact on maternal TL dynamics. Full article

Propyl-paraben (PrP) is a common preservative found in cosmetics and pharmaceutical products. It is classified as a category 1 endocrine-disrupting compound, which highlights the importance of efficiently removing it from water during treatment processes. This study investigates the potential of using Leptolyngbya sp. dominated cyanobacterial biomass residues, in both their raw and hydrothermally treated (hydrochar) forms, for the removal of PrP from aqueous media. Batch and fixed-bed column experiments were carried out under varying conditions to assess adsorption kinetics and equilibrium behavior. Both raw biomass and hydrochar exhibited satisfactory PrP removal, achieving maximum adsorption capacities of 224.58 and 258.55 mg/g respectively, at 10 mg/L initial PrP concentration and 23.33 mg/L adsorbent dosage. Equilibrium data were best described by the Freundlich isotherm model, indicating a heterogeneous surface and multilayer adsorption. The kinetic analysis revealed that the adsorption behavior, for both adsorbents, was best described by the pseudo-second-order model, while the thermodynamic evaluation revealed negative ΔH° and ΔS° values, confirming an exothermic, physisorption-driven process. The adsorption mechanism was further investigated through surface characterization techniques, including Fourier Transform Infrared Spectroscopy, Scanning Electron Microscopy, N₂ physisorption, and zeta potential analysis. The findings demonstrate the potential of microalgal biomass as a low-cost, sustainable biosorbent, for emerging contaminants, reinforcing its role in advanced water treatment and circular economy strategies. Full article

Aquifers are increasingly threatened by the uncontrolled release of non-biodegradable chemicals derived from anthropogenic activities. The development of new remediation strategies has therefore focused on the use of sustainable adsorbent materials, including synthetic organic hydrogels and biochars produced from agricultural residues. In this study, the removal of two organic pollutants, the herbicide Metribuzin (MEB) and Propyl Paraben (PrP), from aqueous environments was investigated using negatively charged hydrogels and biochars derived from lime peel, respectively. Propyl Paraben (PrP) and Metribuzin (MEB) are among the pollutants frequently found in aquatic environments, and the effective and sustainable removal approaches remain under investigation. The hydrogels studied (P(DMAM co-ANax)) were based on sodium methacrylate (ANa) copolymerized with N,N-dimethylacrylamide (DMAM). The adsorption performance of the materials was evaluated through UV-Visible absorption spectrophotometry and High-Performance Liquid Chromatography (HPLC). The results of this study showed that the hydrogel achieved a very high removal efficiency for MEB, which was over 80% for the concentration range studied (max $Q_e$ = 0.386 mg/g). Similar behavior was also recorded for the biochar from lime peel, which achieved almost complete removal of PrP (~100%) at the lowest concentrations of the contaminant (5 mg/L) and maintained high removal rates (78%) at 10 mg/L (max $Q_e$ = 0.187 mg/g). These results demonstrate the potential of both types of materials to efficiently remove the studied contaminants from water, indicating their suitability for environmental remediation applications. This work contributes to the development of cost-effective and eco-friendly adsorbents for the treatment of water pollution caused by emerging organic compounds. Full article

(1) Background: Few studies have examined gestational paraben exposure and early childhood neurodevelopment. We evaluated associations between gestational exposure to methyl, ethyl and propyl paraben and neurodevelopment via the Child Behavior Checklist (CBCL) administered at ages 2, 3, and 4 years. (2) Methods: Gestational exposures were assessed using pooled prenatal urine samples from five time points across pregnancy. CBCL outcomes included internalizing, externalizing, and sub-scale scores. Covariate-adjusted generalized linear regression was employed to assess individual paraben exposures. Mixture analysis was performed using Bayesian Kernel Machine Regression and Quantile g-computation. (3) Results: In individual paraben analyses, each paraben was associated with increased externalizing behaviors, particularly ethylparaben (age 2: β = 0.40, 95% CI = −0.02, 0.83; age 3: β = 0.42, 95% CI = −0.19, 0.01; age 4: β = 0.18, 95% CI = −0.34, 0.70), ADHD problems at age 2 (β = 0.21, 95% CI = 0.05, 0.37), and both aggressive behavior (β = 0.38, 95% CI = 0.01, 0.74) and oppositional defiant problems (β = 0.25, 95% CI = 0.09, 0.41) at age 3. All three parabens were also associated with a reduction in withdrawn symptoms for males, especially at age 2 (ethylparaben: β = −0.09, 95% CI = −0.01, 0.85; methylparaben: β = −0.20, 95% CI = −0.34, −0.05; propylparaben: β = −0.13, 95% CI = −0.24, −0.03). The parabens mixture was associated with elevated scores in multiple CBCL subscales, though only association with oppositional defiant scores at age 3 reached significance in both BKMR (change in score when all components are at 50th percentile values compared with their 75th percentile values = 0.15; 95% CI = 0.01, 0.29) and quantile g-computation (β = 0.33, 95% CI = 0.02, 0.65), driven primarily by ethylparaben. (4) Conclusions: Individual parabens and the paraben mixture showed significant association with domains of childhood neurodevelopment, with possible detriments especially evident (a) at earlier time points, (b) in male children, and (c) in terms of externalizing behaviors. Full article

Background: Natural alternatives are becoming more popular as a result of health risks associated with synthetic preservatives in pharmaceuticals. Because of its antibacterial properties, Psidium guajava (L.) leaf extract is a practical choice for sustainable preservation. Objectives: The aim of this research is to evaluate the efficacy of Psidium guajava (L.) leaf extract as a 10% (w/w) natural preservative in five different base formulations: creams (clotrimazole cream, permethrin cream, and gentamicin cream) and gels (indomethacin emulgel and ibuprofen gel). Methods: Over the course of 28 days, antimicrobial activity against Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli, Aspergillus brasiliensis, and Candida albicans was evaluated. In accordance with USP/BP guidelines, three months of accelerated conditions (40 ± 2 °C/75% ± 5% RH) were used to assess chemical, physical, and microbiological stability. The stability of the active component was examined using HPLC. Results: Our findings showed that the extract completely inhibited the growth of tested bacterial species in clotrimazole cream, permethrin cream, gentamicin cream, and indomethacin emulgel, demonstrating significant antibacterial activity across all formulations. However, the antifungal activity was restricted. The preservation effectiveness criterion (bacterial/yeast counts < 10 CFU, mold < 20 CFU) was only fulfilled by ibuprofen gel and clotrimazole cream. Although there were color changes, stability tests verified that the active components such as ibuprofen (reduced from 97.5% to 92%) and clotrimazole (reduced from 99.9% to 95%) decomposed minimally and had acceptable physical characteristics. Particularly against fungus, the extract was surpassed by chemical preservatives (methyl/propyl paraben). Conclusions: Certain semi-solid pharmaceuticals can benefit from the stability and antimicrobial protection provided by guava leaf extract, a natural preservative. The weak antifungal activity of the guava leaf extract emphasizes the necessity for specific improvements in the formulation. Full article

Furosemide (FUR) is a loop diuretic widely used in pediatric care. However, no standardized oral liquid formulation exists due to degradation concerns, particularly the formation of furosemide-related compound B (FUR-B). This study aimed to develop and validate the HPLC method for the simultaneous quantification of FUR, FUR-B, methylparaben (MP), and propylparaben (PP) in pediatric extemporaneous oral solutions. Chromatographic separation was achieved using a Symmetry^® C18 column (4.6 × 250 mm, 5 µm) with a mobile phase of 0.1% acetic acid in water and acetonitrile (60:40, v/v) at 1.0 mL/min of flow with injection volume at 10 µL. Detection at 272 nm provided optimal sensitivity, especially for low concentrations of FUR-B. Forced degradation confirmed baseline separation of FUR from its degradation products. The condition showed high linearity (R² > 0.995), accuracy (recoveries 98.2–101.0%), and precision (RSD ≤ 2%). Robustness and ruggedness tests under varied conditions, analysts, and intra-day yielded consistent performance. Application to extemporaneous formulations showed that refrigeration (2–8 °C) retained initial composition, while elevated temperatures (30 °C and 40 °C) promoted FUR degradation, with FUR-B increasing to 6.84% after 90 days and greater MP and PP degradation. This validated method offers a reliable analytical tool for monitoring chemical changes and supporting quality control of pediatric FUR extemporaneous formulations. Full article

Parabens are recognized as emerging contaminants. Used in the pharmaceutical and cosmetic industries, they present significant ecological risks to aquatic ecosystems. This study evaluated the effects of two parabens—methyl 4-hydroxybenzoate (methylparaben) and propyl 4-hydroxybenzoate (propylparaben)—both individually and as a mixture on daphnids. Through a series of controlled exposure experiments, phenotypic endpoints, including mortality, feeding behaviour, and enzymatic activity, were measured. The results demonstrate that propyl paraben and the mixture of propyl and methyl paraben exhibit greater toxic potential compared to methyl paraben alone. We observed a dose-dependent impact on key enzymes, indicating significant metabolic disruption. These findings underscore the necessity of utilizing model systems to investigate the complex interactions and cumulative impacts of pollutant mixtures in aquatic environments. Furthermore, this study provides critical insights regarding the underlying toxicity mechanisms of parabens, highlighting the need for comprehensive water quality monitoring and risk assessment frameworks to address the challenges posed by emerging contaminants. Full article

In South Korea, a Human Biomonitoring (HBM) program, known as the Korean National Environmental Health Survey (KoNEHS), was launched in 2009. This study aims to provide an overview of environmental chemical exposures in South Korea based on data from the KoNEHS cycle 4 (2018–2020). To ensure population representativeness, Koreans aged 3 years and older were recruited from 426 sites across the country. A total of 6381 participants joined in the collection of biospecimens, which were subsequently analyzed for 33 environmental chemicals or their metabolites, including nine that were not included in the previous cycle. The five most common PFASs were detected in more than 99.7% of the participants. The GM of serum PFOS was the highest in adults at 15.1 µg/L (13.9, 16.4) and in adolescents at 7.97 µg/L (7.42, 8.56). In adults, there was a gradual decrease in the detection rate and concentration of some heavy metals and phthalate metabolites. In children and adolescents, the detection rate of BPA in urine decreased, while the rate of its substitutes BPF and BPS increased, and the rate of propyl paraben in urine decreased significantly. The results of the KoNEHS cycle 4 indicate that exposure levels to certain environmental chemicals are still high, highlighting further monitoring and on-going surveys to determine their trends, especially for newly investigated substances, such as PFASs. Full article

In this work, we describe compatibility assessments of a recombinant, trivalent non-replicating rotavirus vaccine (t-NRRV) candidate with a mock trivalent Sabin inactivated polio vaccine (t-sIPV). Both t-sIPV and t-NRRV are incompatible with thimerosal (TH), a preservative commonly used in pediatric pentavalent combination vaccines (DTwP-Hib-HepB) distributed in low- and middle-income countries (LMICs), preventing the development of a heptavalent combination. The compatibility of t-NRRV with a mock DTwP-Hib-HepB formulation is described in a companion paper. This case study highlights the analytical and formulation challenges encountered when combining a mock t-sIPV vaccine (unadjuvanted) with Alhydrogel^® (AH) adjuvanted t-NRRV. Selective and stability-indicating competition ELISAs were implemented to monitor antibody binding to each of the six antigens (±AH). Simple mixing caused the undesired desorption of t-NRRV from AH with the concomitant binding of t-sIPV to AH. Although the former effect was mitigated by dialyzing sIPV bulks, decreased sIPV storage stability was observed at accelerated temperatures in the bivalent combination with a rank-ordering of P[8] > P[6] > P[4] and sIPV3 > sIPV2 > sIPV1. The compatibility of AH-adsorbed t-sIPV with alternative preservatives was evaluated, and parabens (methyl, propyl) were identified for potential use in this multi-dose bivalent formulation. Along with a companion paper, the lessons learned are discussed to facilitate the future formulation development of pediatric combination vaccines with new antigens. Full article

The purpose of this work was to develop a novel topical formulation of econazole nitrate based on gel that can be easily scaled up in one pot for the potential treatment of fungal and yeast infections. Econazole nitrate, a topical antifungal, is used to treat tinea versicolor, tinea pedis, and tinea cruris. Compared to applying cream or ointment, topical gels offer numerous advantages, one of which is that the drug is released more quickly to the intended site of action. A viscous mixture of propylene glycol, Capmul^® MCM C8, methyl and propyl paraben, and econazole nitrate were mixed together before being formulated into the optimized Carbopol^® gel bases. The gel’s color, appearance, and homogeneity were assessed visually. For every formulation, the drug content, pH, viscosity, spreadability, and gel strength were characterized. The cup plate diffusion method was used to evaluate the anti-fungal activity of the prepared formulations. To assess the behavior of the developed system, studies on in vitro release and mechanism were conducted. The manufactured formulations were transparent, pale yellow, and exhibited excellent homogeneity. The pH of each formulation was roughly 6.0, making them suitable for topical use. The concentration of Carbopol^® 940 resulted in a significant increase in viscosity and gel strength but a significant decrease in spreadability. It was demonstrated that the prepared formulations inhibited the growth of Candida albicans and Aspergillus fumigatus. In contrast, the standard blank gel showed no signs of antifungal action. By increasing the concentration of Carbopol^® 940, the in vitro release profile of econazole nitrate significantly decreased. Following the Korsmeyer–Peppas model fitting, all formulations exhibited n values greater than 0.5 and less than 1, indicating that diffusion and gel swelling control econazole nitrate release. Full article

Increasing evidence has been published over recent years on the implication of endocrine-disrupting chemicals (EDCs), including parabens and benzophenones in the pathogenesis and pathophysiology of endometriosis. However, to the best of our knowledge, no study has been published on the ways in which exposure to EDCs might affect cell-signaling pathways related to endometriosis. We aimed to describe the endometriotic tissue expression profile of a panel of 23 genes related to crucial cell-signaling pathways for the development and progression of endometriosis (cell adhesion, invasion/migration, inflammation, angiogenesis, and cell proliferation/hormone stimulation) and explore its relationship with the exposure of patients to parabens (PBs) and benzophenones (BPs). This cross-sectional study included a subsample of 33 women with endometriosis from the EndEA study, measuring their endometriotic tissue expressions of 23 genes, while urinary concentrations of methyl-, ethyl-, propyl-, butyl-paraben, benzophenone-1, benzophenone-3, and 4-hydroxybenzophenone were determined in 22 women. Spearman’s correlations test and linear and logistic regression analyses were performed. The expression of 52.2% of studied genes was observed in >75% of endometriotic tissue samples and the expression of 17.4% (n = 4) of them in 50–75%. Exposure to certain PB and BP congeners was positively associated with the expression of key genes for the development and proliferation of endometriosis. Genes related to the development and progression of endometriosis were expressed in most endometriotic tissue samples studied, suggesting that exposure of women to PBs and BPs may be associated with the altered expression profile of genes related to cellular pathways involved in the development of endometriosis. Full article

Exposure to chemical substances has always been a matter of concern for the scientific community. During the last few years, researchers have been focusing on studying the effects resulting from combined exposure to different substances. In this study, we aimed to determine the DNA damage caused after chronic and combined exposure to substances characterized as endocrine disruptors using comet and micronuclei assays, specifically glyphosate (pure and commercial form), bisphenol A, parabens (methyl-, propyl- and butylparaben), triclosan and bis (2-ethylhexyl) phthalate. The highest mean tail intensity was observed in the group exposed to a high-dose (10 × ADI) mixture of substances (Group 3), with a mean value of 11.97 (11.26–13.90), while statistically significant differences were noticed between the groups exposed to low-dose (1 × ADI) (Group 2) and high-dose (10 × ADI) (Group 3) mixtures of substances (p = 0.003), and between Group 3 and both groups exposed to high doses (10 × ADI) of the pure and commercial forms of glyphosate (Groups 4 (p = 0.014) and 5 (p = 0.007)). The micronuclei assay results were moderately correlated with the exposure period. Group 5 was the most impacted exposure group at all sampling times, with mean MN counts ranging between 28.75 ± 1.71 and 60.75 ± 1.71, followed by Group 3 (18.25 ± 1.50–45.75 ± 1.71), showing that commercial forms of glyphosate additives as well as mixtures of endocrine disruptors can enhance MN formation. All exposure groups showed statistically significant differences in micronuclei counts with an increasing time trend. Full article

Cosmetic products contain preservatives to prevent microbial growth. The various types of preservatives present in skincare products applied on the skin induce many side effects. We tested several types of preservatives such as phenoxyethanol, methyl paraben, propyl paraben, imidazolidinyl urea (IU), the composition of gluconolactone and sodium benzoate (GSB), diazolidinyl urea (DU), and two grapefruit essential oils, one of which was industrially produced and a second which was freshly distilled from fresh grapefruit peels. This study aimed to find the relationship between preservative concentration, cell growth, collagen secretion, and cell viability. We hypothesized that these products induced a decrease in collagen secretion from human dermal fibroblasts. Our research, for the first time, addressed the overall effect of other preservatives on skin extracellular matrix (ECM) by studying their effect on metalloproteinase-2 (MMP-2) activity. Except for cytotoxicity and contact sensitivity tests, there are no studies of their effect on skin ECM in the available literature. These studies show potential antimicrobial activity, especially from the compounds IU and DU towards reference bacteria and the compounds methyl paraben and propyl paraben against reference fungi. The MTS test showed that fibroblasts are more sensitive to the tested group of preservatives than keratinocytes, which could be caused by the differences between the cells’ structures. The grapefruit oils exhibited the most cytotoxicity to both tested cell lines compared to all considered preservatives. The most destructive influence of preservatives on collagen synthesis was observed in the case of IU and DU. In this case, the homemade grapefruit oil turned out to be the mildest one. The results from a diverse group of preservatives show that whether they are natural or synthesized compounds, they require controlled use. Appropriate dosages and evaluation of preservative efficacy should not be the only aspects considered. The complex effect of preservatives on skin processes and cytotoxicity is an important topic for modern people. Full article

Parabens and bisphenol A are synthetic compounds found in many everyday objects, including bottles, food containers, personal care products, cosmetics and medicines. These substances may penetrate the environment and living organisms, on which they have a negative impact. Till now, numerous studies have described parabens and BPA in humans, but knowledge about terrestrial wild mammals’ exposure to these compounds is very limited. Therefore, during this study, the most common concentration levels of BPA and parabens were selected (such as methyl paraben—MeP, ethyl paraben—EtP, propyl paraben—PrP and butyl paraben—BuP) and analyzed in guano samples collected in summer (nursery) colonies of greater mouse-eared bats (Myotis myotis) using liquid chromatography with the tandem mass spectrometry (LC-MS-MS) method. MeP has been found in all guano samples and its median concentration levels amounted to 39.6 ng/g. Other parabens were present in smaller number of samples (from 5% for BuP to 62.5% for EtP) and in lower concentrations. Median concentration levels of these substances achieved 0.95 ng/g, 1.45 ng/g and 15.56 ng/g for EtP, PrP and BuP, respectively. BPA concentration levels did not exceed the method quantification limit (5 ng/g dw) in any sample. The present study has shown that wild bats are exposed to parabens and BPA, and guano samples are a suitable matrix for studies on wild animal exposure to these substances. Full article